/// @file
/// @author David Pilger <dpilger26@gmail.com>
/// [GitHub Repository](https://github.com/dpilger26/NumCpp)
///
/// License
/// Copyright 2018-2022 David Pilger
///
/// Permission is hereby granted, free of charge, to any person obtaining a copy of this
/// software and associated documentation files(the "Software"), to deal in the Software
/// without restriction, including without limitation the rights to use, copy, modify,
/// merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
/// permit persons to whom the Software is furnished to do so, subject to the following
/// conditions :
///
/// The above copyright notice and this permission notice shall be included in all copies
/// or substantial portions of the Software.
///
/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
/// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
/// PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
/// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
/// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
/// DEALINGS IN THE SOFTWARE.
///
/// Description
/// Create an array of the given shape and populate it with
/// random samples from the "triangle" distribution.
///
#pragma once

#ifndef NUMCPP_NO_USE_BOOST

#include <algorithm>
#include <string>

#include "boost/random/triangle_distribution.hpp"

#include "NumCpp/Core/Internal/Error.hpp"
#include "NumCpp/Core/Internal/StaticAsserts.hpp"
#include "NumCpp/Core/Shape.hpp"
#include "NumCpp/NdArray.hpp"
#include "NumCpp/Random/generator.hpp"

namespace nc
{
    namespace random
    {
        namespace detail
        {
            //============================================================================
            // Method Description:
            /// Single random value sampled from the "triangle" distribution.
            /// NOTE: Use of this function requires using the Boost includes.
            ///
            /// NumPy Reference:
            /// https://docs.scipy.org/doc/numpy/reference/generated/numpy.random.triangular.html#numpy.random.triangular
            ///
            /// @param generator: instance of a random number generator
            /// @param inA
            /// @param inB
            /// @param inC
            /// @return NdArray
            ///
            template<typename dtype, typename GeneratorType = std::mt19937>
            dtype triangle(GeneratorType& generator, dtype inA = 0, dtype inB = 0.5, dtype inC = 1)
            {
                STATIC_ASSERT_FLOAT(dtype);

                if (inA < 0)
                {
                    THROW_INVALID_ARGUMENT_ERROR("input A must be greater than or equal to zero.");
                }

                if (inB < 0)
                {
                    THROW_INVALID_ARGUMENT_ERROR("input B must be greater than or equal to zero.");
                }

                if (inC < 0)
                {
                    THROW_INVALID_ARGUMENT_ERROR("input C must be greater than or equal to zero.");
                }

                const bool aLessB = inA <= inB;
                const bool bLessC = inB <= inC;
                if (!(aLessB && bLessC))
                {
                    THROW_INVALID_ARGUMENT_ERROR("inputs must be a <= b <= c.");
                }

                boost::random::triangle_distribution<dtype> dist(inA, inB, inC);
                return dist(generator);
            }

            //============================================================================
            // Method Description:
            /// Create an array of the given shape and populate it with
            /// random samples from the "triangle" distribution.
            /// NOTE: Use of this function requires using the Boost includes.
            ///
            /// NumPy Reference:
            /// https://docs.scipy.org/doc/numpy/reference/generated/numpy.random.triangular.html#numpy.random.triangular
            ///
            /// @param generator: instance of a random number generator
            /// @param inShape
            /// @param inA
            /// @param inB
            /// @param inC
            /// @return NdArray
            ///
            template<typename dtype, typename GeneratorType = std::mt19937>
            NdArray<dtype>
                triangle(GeneratorType& generator, const Shape& inShape, dtype inA = 0, dtype inB = 0.5, dtype inC = 1)
            {
                STATIC_ASSERT_FLOAT(dtype);

                if (inA < 0)
                {
                    THROW_INVALID_ARGUMENT_ERROR("input A must be greater than or equal to zero.");
                }

                if (inB < 0)
                {
                    THROW_INVALID_ARGUMENT_ERROR("input B must be greater than or equal to zero.");
                }

                if (inC < 0)
                {
                    THROW_INVALID_ARGUMENT_ERROR("input C must be greater than or equal to zero.");
                }

                const bool aLessB = inA <= inB;
                const bool bLessC = inB <= inC;
                if (!(aLessB && bLessC))
                {
                    THROW_INVALID_ARGUMENT_ERROR("inputs must be a <= b <= c.");
                }

                NdArray<dtype> returnArray(inShape);

                boost::random::triangle_distribution<dtype> dist(inA, inB, inC);

                std::for_each(returnArray.begin(),
                              returnArray.end(),
                              [&generator, &dist](dtype& value) -> void { value = dist(generator); });

                return returnArray;
            }
        } // namespace detail

        //============================================================================
        // Method Description:
        /// Single random value sampled from the "triangle" distribution.
        /// NOTE: Use of this function requires using the Boost includes.
        ///
        /// NumPy Reference:
        /// https://docs.scipy.org/doc/numpy/reference/generated/numpy.random.triangular.html#numpy.random.triangular
        ///
        /// @param inA
        /// @param inB
        /// @param inC
        /// @return NdArray
        ///
        template<typename dtype>
        dtype triangle(dtype inA = 0, dtype inB = 0.5, dtype inC = 1)
        {
            return detail::triangle(generator_, inA, inB, inC);
        }

        //============================================================================
        // Method Description:
        /// Create an array of the given shape and populate it with
        /// random samples from the "triangle" distribution.
        /// NOTE: Use of this function requires using the Boost includes.
        ///
        /// NumPy Reference:
        /// https://docs.scipy.org/doc/numpy/reference/generated/numpy.random.triangular.html#numpy.random.triangular
        ///
        /// @param inShape
        /// @param inA
        /// @param inB
        /// @param inC
        /// @return NdArray
        ///
        template<typename dtype>
        NdArray<dtype> triangle(const Shape& inShape, dtype inA = 0, dtype inB = 0.5, dtype inC = 1)
        {
            return detail::triangle(generator_, inShape, inA, inB, inC);
        }
    } // namespace random
} // namespace nc

#endif // #ifndef NUMCPP_NO_USE_BOOST
